/**
 * Created by shuai on 16/9/8.
 */
function $(id){
    return typeof id==='string'?document.getElementById(id):id;
}

window.onload=tab;
function tab(){
    var index=0;
    var timer=null;
    var lis=$('notice-tit').getElementsByTagName('li');
    var divs=$('notice-con').getElementsByTagName('div');
    for(var i=0;i<lis.length;i++){
        lis[i].id=i;
        lis[i].onmouseover=function(){
            clearInterval(timer);
            changeOption(this.id);
        }
        lis[i].onmouseout=function(){
            timer=setInterval(autoPlay,2000);
        }
    }

    if(timer){
        clearInterval(timer);
        timer=null;
    }

    timer=setInterval(autoPlay,2000);

    function autoPlay(){
        index++;
        if(index>=lis.length){
            index=0;
        }
        changeOption(index);
    }

    function changeOption(curIndex){
        for(var j=0;j<lis.length;j++){
            lis[j].className='';
            divs[j].style.display='none';
        }
        lis[curIndex].className='select';
        divs[curIndex].style.display='block';
        index=curIndex;
    }
}